Atari ST Overview History Description Screenshots

The Atari ST was a typical second-generation home computer, based on the Motorola 68000 chip set, shipping with 1/2 a megabyte of RAM or more, and using 3.5" floppy disks as the normal storage medium. In these respects it was similar to a number of other contemporary machines, including the Apple Macintosh, Commodore Amiga and, to some extent, the Acorn Archimedes. The ST was generally less expensive and somewhat faster than the competition, but had lower quality graphics and sound support.

The ST was primarily a competitor to the Commodore Amiga systems. This platform rivalry was often reflected by the owners and was most prominent in the Demo Scene. Where the Amiga had custom hardware which gave it the edge in the games and videowork market, the ST was generally cheaper and slightly faster at basic operation. Thanks to its built-in MIDI ports enjoyed success as a music sequencerIn the field of electronic music, a sequencer was originally any device that recorded and played back a sequence of control information for an electronic musical instrument. Early analog music sequencers used control voltage/trigger interface, but have ge and controllerIn control theory, a controller is a device that attempts to control states or outputs of a dynamic system. Generally, this is accomplished using feedback to reject disturbances to the system. This is called closed-loop control. Open-loop control is also of musical instrumentA musical instrument is a device that has been constructed or modified with the purpose of making music. In principle, anything that somehow produces sound can serve as a musical instrument, but the expression is reserved generally to items that have thats among amateurs and professionals alike, being used in concert by bands such as Tangerine DreamThis article is about the German band Tangerine Dream. Tangerine Dream is also the name of the Japanese band Do As Infinity's first single, released on September 29, 1999. For information regarding the Japanese band and their music, see: Do As Infinity Ta . In some markets, particularly GermanyThe Federal Republic of Germany ( German: Bundesrepublik Deutschland is one of the world's leading industrialized countries, located in the middle of the European Union. It is bordered to the north by the North Sea, Denmark and the Baltic Sea, to the east, the machine gained a strong foothold as a small business machine for CAD and Desktop publishing work.

Since Atari pulled out of the computer market there has been a market for powerful TOS-based machines (clones). Like most "retro" computers the Atari enjoys support in the emulator scene.

2 History

Atari had created two released machines in the form of the Atari 2600 console (also known as VCS) and the various Atari 8-bit based home computers. Both of these lines were created around the 6502 CPU and included a number of additional chips assisting this rather basic, but cost-effective CPU in providing graphics and sound. In fact the 8-bit machines had originally intended to be the replacement for the 2600, but they were later "re-purposed" as home computers to cash in on that market segment's much higher selling prices.

As Atari grew and the management was shuffled by Warner (their parent company), the creators of the 2600 and 8-bit machines eventually got fed up and left. A group of them led by Jay Miner formed a small think tank called Amiga in 1982 and set about creating the third generation machine, this time based on the much more powerful 68000 CPU.

During this time, the home computer market started to slow down, and the video game market underwent the great video game crash of 1983. Warner management decided to "get out" and started looking to sell Atari outright. Meanwhile many of the same effects were in the process of decimating Commodore International. An argument involving Commodore's chairman Irving Gould, and Jack Tramiel ensued, resulting in Tramiel's immediate departure from Commodore in January of 1984.

Tramiel immediately formed a holding company, Tramiel Technology, and brought in a number of ex-Commodore staff to start a rush project to develop a new, high-performance home computer. While this team worked on the design, Tramiel started making overtures to buy Atari from Warner. The design team considered "one-upping" the Macintosh by using a full 32-bit chip, namely the NS32032, but in talks National Semiconductor couldn't supply the numbers of price the project needed. In retrospect this proved to be lucky, a prototype built on the NS32032 proved to be slower than the 16-bit 68000.

The basic hardware design quickly "gelled" into a form that was almost identical to the ST that eventually shipped. The design used many off-the-shelf parts, as opposed to the large number of custom VLSI chips used in most systems of the era. Disk drive support was provided by a standard Western Digital chip and sound from a Yamaha YM2149, a clone of the common but fairly basic General Instruments AY-3-8910. The only custom chips were a simple memory controller, the "Shifter" graphics processor and the GLUE interrupt handler.

At about the same time, Amiga were desperate for a buyer or investor, and the "Warner owned" Atari had paid Amiga for development work (see: "TOP SECRET: Confidential Atari-Amiga Agreement"). In return Atari was to get one-year exclusive use of the design. By May Tramiel had secured his funding, bought the remains of Atari from Warner for a very low price, and set about re-creating his empire.

When Tramiel took over the company he tried to leverage this and take ownership of the Amiga properties. Right under the noses of Atari, and at the 11th hour for Amiga, Commodore purchased Amiga lock, stock, and barrel. Tramiel was furious, and the resulting court case lasted for years. In the meantime this left Atari with an incomplete 16-bit design, while Commodore would soon have the best.

Work thus continued with the design started at Tramiel Technology. With the basic design complete, the team started looking at solutions for the operating system. Soon after the buyout Microsoft approached Tramiel with the suggestion that they port Windows to the platform, but the delivery date was out about two years, far too long for their needs. Another possibility was Digital Research, who were working on a new GUI-based system then known as Crystal, soon to become GEM. A final possibility was to write a new system in-house, but this was eventually rejected due to risk.

DR seemed generally uninterested in porting the system themselves, so a team from Atari was sent to their Monterey headquarters to do it themselves. They were given the latest versions of the Intel 8086 code from their DR counterparts, and would port it to the 68000 as quickly as possible. A version, running on top of CP/M-68K, was available just in time for the January 1985 CES, where the ST was introduced.

CP/M-68K was essentially a direct port of CP/M's original, and very old, operating system. By 'modern' standards of 1985, it was rather outdated both in terms of command structure, and that it didn't support hierarchical file systems. DR was also in the process of building a new DOS-like operating system specifically for GEM, GEMDOS, and there was some discussion of whether or not a port of GEMDOS could be complete in time for product delivery in June. The decision was eventually taken to port it, resulting in a GEM/GEMDOS system Atari referred to as TOS. This was benefital to the system, as it allowed the ST to read and write standard IBM PC disks.

The design shipped in June 1985 as the 520 ST. The machine had gone from concept to store shelves in a little under a year. Atari had originally intended to release versions with 128 KB and 256 KB of RAM as the 130 ST and 260 ST respectively, but the rapidly falling prices of RAM at the time led them to cancel these versions and it was released with 512K only. In 1986 the 1040STF shipped with 1MB of RAM and featured an integral PSU and double sided floppy-disk drive. However the ST remained generally the same internally over the majority of its several-year lifespan.

3 Description

The 520ST was an all-in-one unit, similar to earlier home computers like the Commodore 64. However by this time the market demanded a "full sized" keyboard, including cursor keys and a numeric keypad. For this reason the 520ST was fairly "boxy", generally oversized for a machine that one had to move around to adjust the keyboard position. Adding to this problem was the number of large cables needed to connect to the peripherals. This problem was addressed to some degree in the follow-on models which included a built-in floppy disk.

Following most machines of the era, and thus differing greatly from earlier Atari designs, the ST used a large number of one-off ports mounted on the rear of the machine. In addition to power and monitor connections, the ST included an RS-232 serial port, a Centronics printer connection, two Atari-standard joystick/mouse ports, a hard drive connector (not SCSI), the floppy disk connector, a cartridge port and the two MIDI ports.

The case followed the Tramiel-Atari design of the era, being basically wedge shaped, with a series of grilles cut into the rear for airflow. Atari machines under the Tramiel rule are marked by infamously "cheap" cases. The original 520 design was quite flimsy, and while the 1040 ST-style case was much stronger, it was also becoming too large and rather unwieldy. In addition the majority of the machines had very poor quality keyboards, so poor that there was a burgeoning third-party market for spring kits to improve the feel. They got the design completely right with the Mega ST series which included a detached high-quality keyboard and stronger case, but this apparently cost too much to produce and the design was not used widely.

An annoying problem concerned the disk drives. Early models were shipped with an external single-sided drive that could store up to 360KB, with an optional double-sided version that stored 720KB for considerably more money. Due to the early sales of so many of the single-sided drives, almost all software would ship on two single-sided disks instead of a single double-sided one, in fear of cutting off all the other owners. This was true even years later, long after the single-sided drives had been taken off the market.

Additionally they had originally intended to include GEM's GDOS hardware abstraction layer, which allowed programs to draw (display, print, etc.) graphics to any supported device with no changes. This allowed developers to write a program for display to the screen, and get high quality printing "for free". However GDOS was not ready at the time the ST started shipping, and while Atari promised to include it as soon as possible, they never did. This left printing support up to the developers, who had to create their own engines for every possible printer.

Similarly the custom " BLiTTER" was to be included to speed the performance of graphics operations on the screen, but this was isolated to their "upscale" machines when it was eventually released years later. As a result, the power of GEM was largely lost on the ST platform, even when GDOS and BLiTTER eventually shipped, it was ignored by developers because it was on so few machines. The STE models initially had serious operating systems conflicts resulting in many applications and games written for the ST line being unusable.

On the plus side the ST was less expensive than most machines, including Macintosh Plus, and tended to be faster than most (external link: price comparison). Largely as a result of the price/performance factor, the ST would go on to be a fairly big seller, notably in markets where the foreign exchange rates amplified prices. For this reason the ST was most popular in Europe, especially in Germany. Also, the very crisp, 640 by 400 pixels picture of its black & white monitor made it popular for small-office applications. In fact, an Atari ST and reasonable terminal emulation software was much cheaper than a Digital VT220 terminal that was normally needed by offices with central computers.

4 Screenshots


GEM (Desktop)	Neochrome	1st Word	STZip
Atari/ Digital Research ( 1985)	Dave Staugas ( 1985)	GST ( 1985)	Vincent Pomey ( 1994)


Dungeon Master	MIDI Maze	Populous	Xenon 2
Mirrorsoft/ FTL ( 1987)	Hybrid Arts ( 1987)	EA/ Bullfrog ( 1989)	Bitmap Brothers/Assembly Line ( 1989)

More screenshots can be found on the Atari ST Games page.

5 Technical specifications

As originally released in the 520 ST:

CPU: Motorola 68000 @ 8 Mhz
RAM: 512 KB
Sound: Yamaha YM2149
Drive: single-sided 3½" floppy disk drive
Ports: TV out (on FM models), MIDI In/Out, RS-232, Printer, Monitor ( RGB and Mono), Extra Disk drive port, Joystick and Mouse ports
Operating System: TOS (Tramiel Operating System) with the GEM (Graphical Environment Manager) GUI
Display modes: 320×200 (16 colour), 640×200 (4 colour), 640×400 (mono), palette of 512 colours

Very early machines included the OS on a floppy disk, but this was quickly replaced with ROM versions instead. Another early addition (after about 6 months) was an RF Modulator that allowed the machine to be hooked to a colour TV when run in it low resolution mode. These models were known as the 520STm.

6 Models

A number of machines were released in the ST family. Here they are, in rough chronological order after the original 520 ST:

520 ST+ - Name for early 520 STs with 1 MB of RAM, but without floppy disk
260 ST - European name for the 520 ST with 512 KB. Used after the release of the 520 ST+ to differentiate the cheaper 512 KB models from the 1 MB models
520 STm - a 520 ST with a built-in modulator for TV output.
520 STfm - a 520 STm with a newly redesigned motherboard in a larger case with a built-in floppy disk drive
1040 STf - a 520 STfm with 1 MB of RAM and a built-in double-sided floppy disk, but without modulator
1040 STfm - a 520 STfm with 1 MB of RAM and a built-in double-sided floppy disk
MEGA2 and MEGA4 - 1040 with either 2 or 4MB of RAM, in a much improved "pizza box" case with a detached keyboard. These models included the BLiTTER chip, but the OS ROM was not upgraded and the extra GEM functionality needed to be booted from disk.
520 STe and 1040 STe - enhanced sound, the BLiTTER chip, and a 4096 color palette, in the older 1040 style all-in-one case
Mega STE - same hardware as 1040 STe except for a faster 16 MHz processor, in the TT case
STacy - A portable (but definitely not laptop) version of the ST. Originally designed to operate on 12 standard C cell flashlight batteries for portability, when Atari finally realized how quickly the machine would use up a set of batteries (the batteries were not rechargable), they simply glued the lid of the battery compartment shut.
ST Book (later version of portable atari)

7 Other models

TT 030 - new machine based on the Motorola 68030 processor running at 32 Mhz, in yet another new case design with a detached keyboard.
Atari Falcon 030 - another '030 based machine like the TT, but in the 1040 style case (yet again) with another upgrade to the graphics, sound, a Motorola 56000 DSP, multitasking OS (on disk) and a LocalTalk port for networking

There was also some unrelased prototypes: Falcon 040 (external link) (based on a Motorola 68040, new case and slots), and STylus (palmtop)

Home > Atari ST

1 Overview

2 History

3 Description

4 Screenshots

5 Technical specifications

6 Models

7 Other models

8 External links

8.1 History

8.2 General

8.3 Emulators

Topics: Atari ST, Overview, History, Description, Screenshots...